/*
 * hello-5.c - Demonstrates command line argument passing to a module.
 */
#include <linux/module.h>	//Needed by all modules
#include <linux/kernel.h>	//Needed for KERN_INFO
#include <linux/moduleparam.h>	//Needed by all modules
#include <linux/init.h>		//Needed for macros
#include <linux/stat.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Cheng Feitian");


static short int myshort = 1;
static int myint = 420;
static long int mylong = 9999;
static char *mystring = "blah";
static int myintArray[2] = {-1,-1};
static int arr_argc = 0;

/*
 *module_param(foo,int,0000)
 *The first param is the parameters name
 *The second param is it's data type
 *The final argument is the permissions bits,
 *for exposing parameters in sysfs (if non-zero) at a later stage.
 */

module_param(myshort,short,S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
MODULE_PARM_DESC(myshort,"A short integer");
module_param(myint,int,S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
MODULE_PARM_DESC(myint,"An integer");
module_param(mylong,long,S_IRUSR);
MODULE_PARM_DESC(mylong,"A long integer");
module_param(mystring,charp,0000);
MODULE_PARM_DESC(mystring,"A character string");

/*
 *module_param_array(name,type,num,perm);
 *The first param is the parameter's (in this case the array's) name
 *The second param is the data type of the elements of the array
 *The third argument is a pointer to the variable that will store the number
 *of elements of the array initialized by the user at module loading time
 *The forth argument is the permission bits
 */
module_param_array(myintArray,int,&arr_argc,0000);
MODULE_PARM_DESC(myintArray,"An array of integers");

static int __init hello_5_init(void)
{
	int i;
	printk(KERN_INFO "Hello,world 5\n==============\n");
	printk(KERN_INFO "myshort is a short integer: %hd\n",myshort);
	printk(KERN_INFO "myint is an integer: %d\n",myint);
	printk(KERN_INFO "mylong is a long integer: %ld\n",mylong);
	printk(KERN_INFO "mystring is a character string: %s\n",mystring);
	for (i = 0;i < (sizeof myintArray / sizeof (int)); i++)
	{
		printk(KERN_INFO "myintArray[%d] = %d\n",i,myintArray[i]);
	}	
	printk(KERN_INFO "got %d arguments for myintArray.\n",arr_argc);
	return 0;
}

static void __exit hello_5_exit(void)
{
	printk(KERN_INFO "Goodbye,world 5\n");
}

module_init(hello_5_init);
module_exit(hello_5_exit);
